Backyard Chickens, Eggs and Salmonella: Are You at Risk?
Updated: 11 March 2021
We’ve all heard of Salmonella at some time in our lives. But what is it?
Salmonella (salmonellosis) is a type of gastroenteritis caused by Salmonella bacteria. Here in Australia, most infections occur after people eat contaminated food.
Think foods containing raw egg such as egg based mayonnaise and cake batter. But - It can also occur after we come into contact with an infected person - or animal.
The Coronavirus lockdown has seen a huge surge in backyard chickens, and therefore backyard eggs. Even if they look healthy - can backyard chickens make you sick?
The good news is we’re here to help you learn how to prevent Salmonella in chickens, their eggs and your family.
You’ll also enjoy the healthiest, tastiest and most ethically-produced eggs possible from your healthy, happy hens.
How do Backyard Chickens Get Salmonella?
Eggs have a shell (obviously!), but the cuticle is the outermost layer of an egg and an egg's natural defense against bacteria.
The cuticle is what gives eggs their shine and seals an egg. Eggs are laid slightly wet, and the cuticle sets as the egg dries. But as it dries, its contents contract like a tiny sponge.
Any Salmonella bacteria on the surface of the shell can potentially enter the egg.
Poultry Eggs-pert Megg Miller describes it as being like a lacquer - it goes on last, protects the egg and gives it its natural shine.
But if chickens lay eggs into a dirty nest, the cuticle can't protect the egg.
What Are The Chances Of Catching Salmonella From My Chickens?
Salmonella can be carried in the environment, in manure, in poultry meat and even eggs. Healthy chickens and sensible hygiene will help keep you safe.
There is much less chance of contamination in eggs, but that does not mean there's no chance.
Dirty nesting boxes (think wet winters!), egg collection, and egg storage are risks for Salmonella transmission through eggs.
Removing the cuticle through soaking or scrubbing eggs can also increase your risk of Salmonella.
How Can Salmonella Spread to People?
How can you get Salmonella from backyard chickens? Salmonella may be found in the yolk or on the shell.
- Salmonella can enter the yolk as the egg is forming in the body of an infected hen. It’s a small risk; however, one Salmonella case in 2020 was linked to a chicken from a commercial egg farm west of Melbourne.
- Far more commonly, bacteria penetrates the eggshell.
How to Prevent Salmonella in Backyard Chickens
There are many ways you can easily prevent infection, and it’s certainly no reason to hold you back from getting a backyard flock!
The fresh eggs you get from your backyard chickens have a lower chance of containing Salmonella than those you buy from the shop - just another reason why we love our free-ranging chickens!
I’m here to reassure you that you can significantly reduce the chance of you or your family becoming sick with Salmonella by following simple food handling and sensible handwashing.
- Keep nesting boxes clean. Do not allow chickens to sleep in nesting boxes.
- Change the nesting box litter regularly.
- Collect eggs regularly, at least daily. Don't allow them to build up and risk them becoming cracked or dirty.
- Separate clean eggs from dirty eggs. Discard cracked, broken eggs, seriously dirty or soiled eggs instantly. It's not worth the risk.
- Don't feed your chicken off or mouldy food especially expired meats which can be a source of Salmonella.
How to Safely Clean Eggs for Home Use
- Clean the egg by buffing them with a clean abrasive pad. Some small egg farms that don't have an egg washing machine use an "Eco Eraser" to scuff the dirt.
- You can also use a warm, damp (not soaking) cloth to wipe the eggs. But The NSW Food Authority says "only a thin layer of moisture that can readily evaporate should be visible on the egg surface". Use a clean part of the cloth for each egg.
- Store eggs in a clean carton or container. Egg farms cannot re-use egg cartons, as they can harbour bacteria from manure or broken eggs.
- Refrigerate clean eggs promptly after cleaning.
- Soak dirty eggs in water. Doing so (cold water is the worst) creates a permeable barrier, ripe for bacteria to enter the egg.
- Refrigerate eggs BEFORE cleaning. The eggshell will contract and may pull any dirt or bacteria from the egg’s surface into the pores when cooled. Egg farms store eggs below 15 °C (with 75% humidity) before cleaning. We also don't want condensation on the egg’s surface (which happens when you go from cold storage to warm room) as this can help bacteria cross the shell into the egg.
Always wash your hands after any contact with chicken manure, chicken coop cleaning and chicken duties in general, and teach your kids to do the same.
Don’t be frightened of your kids touching the chooks! Just practice basic hygiene.
I hope this article has helped you learn how to avoid Salmonella with backyard chickens. Enjoy your chooks. The health benefits of keeping chickens far outweigh any health risks.
Want your chickens to be the healthiest and happiest they can be? I offer backyard chicken workshops, online programs, phone coaching and in-person support to families, schools and free-range egg farmers.
Drop me a line - firstname.lastname@example.org, comment below or visit our Facebook page.
Elise McNamara, Chicken Consultant & Educator.
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